Photoelectric weft detector for looms



D@ 16, 1947. o, v, PAYNE 2,432,793 PHOTOELECTRIC WEFT DFI'ECTOR vFOR tLC'MS Filed Jupe 3Q, 1945 l 5 sheets-sheet 1 M 1L FIGA IO/ I IN V EN TOR.

BY i v V aM/ i ATTORNEQ Dec. 16, 1947. of v, PAYNE 43H93 PHOTOELCTRIG WEFT DETECTOR FOR LOOMS Filed June 30, 1945 I I5 Sheets-Sheet 2 INVENiToR.

BY A TTO/P/VEQ' Dec. 16, 1947. opv. PAYNE 2,432,793

PHoToELEcTRIc wEFT DETECTOR FOR Looms Filed June 5o, 1945 5 sheets-sheet 3 I N VEN TOR.

BY i l ATOQ/v y Patented Dec. 16, 1947 i 2,432,793 PHOTOELECTRIC WEFT DETECTOR FOB LOOMS Oscar V. Payne, Leicester, Mass.,

Crompton & Knowles Loom Works,

assignor to Worcester,

Mass., a corporation of Massachusetts Application June ao, 1945, serial N0. 602,434 '22 claims. (or. 139-213) This invention relates to weft detecting mechanisms for looms and it is the general object of the invention to provide a photoelectrically operating system including a transparent-bobbin.`

In the weaving of very i'lne wefts it is desirable to employ a form of weft detector which will cause a minimum of' abrasion to the weft during the detecting operation. Photoelectric weft detecting systems have been proposed heretofore, but so far as I am aware they have employed bobbins made of opaque material. It is an important objectA of the present invention to provide such a detecting system employing a bobbin made of transparent material and so constructed that a beam of light can move outwardly through th'e bobbin barrelfrom a point within the bobbin for the purpose of actuating a photoelectric cell when theweft is exhausted.

It is a further object of my present invention to provide a bobbin for a photoelectrically controlled detector system wherein a reflector within the bobbin directs a beam of light outwardly through the transparent bobbin toward a photoelectric cell.

In weft replenishing looms it is customary to employ a. shuttle having bobbin holding clips which are adjacent to a bobbin guide having a surface inclined downwardly and toward the longitudinal center of the shuttle. The purpose of this surface is to assist the bobbin t become properly held by the shuttle should the latter be slightly misplaced. It is another object of my present invention to provide the inclined bobbin guide with a reflecting surface which will reect albeam of light along the axis of the bobbin to the aforesaid reflector. In this connection I provide light source means which causes a beam of light to be projected downwardly against the inclined surface whenever the shuttle is completely boxed. By this latter arrangement the shuttle by its entry into the system moves a part of the optical system including the inclined reflecting surface into operative position.

With these and other objects in view which will appear as the descriptionproceeds, my invention resides in the combination and arrangement of parts hereinafter described and set forth.

In the accompanying drawings, wherein a convenient embodiment of my invention is set forth, Fig, 1 is a side elevation of a loom having my invention applied thereto, the shuttle box and lay being in section,

Fig. 2 is an enlarged side elevation of the reserve bobbin magazine shown from the center of the loom, the lay and shuttle box being in section,

Fig. 3 is a plan view looking downwardly on the shuttle along the line 33, Fig. 2 on an enlarged scale, the front wall and part of the shuttle box being in section,

Fig. 4 is a'. front elevation `looking in the direction of arrow 4, Fig. 2, on an enlarged scale, and indicating part of the optical system of the invention, the bobbin being in section,

Fig. 5 is a detailedvertical transverse section on line 5-5 of Fig. 3, i

Fig. 6 is a vertical section through the box or casing containing certain of the electrical devices used with the invention, and

Fig. '7 is a diagrammatic view of the electric u circuits used with the invention.

Referring particularly to Figs. 1 and 2, I have shown a loom frame l0, lay Il, top shaft l2, lay connector i3 and bottom shaft I4. The lay is provided with a shuttle box i5 to receive a shuttle S which when boxed lies between a box back IB and shuttle binder il. The front wall of the shuttle is provided with a horizontal slot I8 which registers'with a similar slot i9 inthe binder when the shuttle is boxed.

The bottom shaft has secured thereto a cam 20 causing periodic oscillation of a lever 2l which by means of the control mechanism 22 causes rising of the forward end of a lever 23 whenthe control mechanism has been set for a replenishing operation. The control mechanism includes a solenoid 24 for the purpose of moving indicator fingers `25 from normal to indicating position. Ordinarily these fingers are out of the path of a dog 26 on lever 2i and as the latter rises the dog passes to one side of the fingers. When the solenoid is energized, however, one or the other of the fingers is moved to indicating position, and the next succeeding upward movement of lever 2i causes the dog 26 to engage a lug 21 on lever 23 and lift the forward end of the latter for the purpose of elevating a'rod 28. The latter controls the transfer mechanism designated generally at ,29.

The magazine M may be of the rocking type and moves about a pivot 30 fixed with respect to the loom frame. Rocking ofl the lever is effected through mechanism designated generally at 3i' and under control of a lever 32 which in turn is controlled by the drop boxes not shown at the opposite end of the loom. Lever 32' is rocked whenever there is a. shifting of said boxes at the opposite end of the loom and operates through in Fig. 1, as viewed 58 rod 33 to determine which of the indicator fingers 25 shall be in position for movement bythe solenoid 24 from normal to indicating position.

The shuttle has bobbin holding clips 35 which receive rings 28 on the bobbin designated generally at B. The shuttle also has a bobbin guide 31 iixed thereto and provided with an inclined surface 38 which extends downwardly and toward the longitudinal center of the shuttle. When the shuttle is properly placed as shown in Fig. 4 the selected bobbin in the magazine will move downwardly into the shuttle without engaging the surface 38. Should the shuttle be improperly placed to the right of the position shown in Fig. 4, the bobbin from the magazinewill engage and be cammed to the right by surface 38 so that the rings 38 can engage the spring clip 35. Th'e shuttle box includes in its construction a mouth cover 48 extending above the door 4l of the shuttle box.

The parts thus far described as well as others shown but not specliically mentioned are all of usual construction and except as mentioned hereinafter, particularly the bobbin and the surface 38, may be made and operated in the usual manner.

In carrying my present invention into eiect I make th'e bobbin B of material which is intrinsically transparent, such as a tough glass or .plasticl The bobbin has a. head 50 carrying the aforesaid rings and also has a short bore 5| extending inwardly from the head. The right end of the bore, see Fig. 4, is provided with a cone 52 having a conical surface 53 which projects toward the head. 'I'his surface may be provided in any manner, but as shown in Fig. 4 it' is made integral with the bobbin. As shown in Fig. 3 the cone 52 is in alignment with the slots I8 and I9.

The surface 88 on the bobbin guide 31 is preferably prepared in such a way that it will be an efiicient light reflector. This result may be accomplished by the use of material inherently capable of taking a high polish, or by coating the surface 38 with some highly reflective metal, or the like.

In order that light may be directed downwardly against the reflector surface 38 I provide a light conducting tube 55 and secure the same as by means of a clip 55 to the cover 40 of the box mouth. The tube may be made of an acrylic plastic known in the trade as Lucite, a methyl methacrylate. The left end of the tube 55 as shown in Fig. 3 may belocated closed to a small container 5 1 in which is located a source of light designated generally at 58. This source of light may be a small bulb and the container is secured as at 58 to a rearward extension 88 of the box back I6. When the shuttle is properly boxed as indicated'in Figs. 3 and 4 a beam of light issuing from the lamp 58 enters the tube 55 and bends around the curved part 8| of the tube and is then directed downwardly toward the reiiector surface 38 from which it is reflected longitudinally of the bobbin to the conical surface 53. From the latter surface the light is directed in several directions, one of them being forwardlythrough the aligned slots I8 and I9 toward a photoelectric tube 85 which is mounted on a small support 66 extending forwardly from the lay.

Under normal operatingconditions the lay reciprocates backwardly and forwardly in the usual manner, the shuttle being picked at top center when the lay is approximately one-half way on its backward stroke and entering the boy I5 when the lay is advancing. The tube 55, being fixed to the shuttle box, has the lower end of the curved part 8| thereof located slightly above the shuttle to be out of the path of the latter as it is boxed. As soon as the shuttle comes to rest light will be directed along the bobbin bore 5| as alreadydescribed, and if suillcient Aweft for continued weaving is present on the bobbin the cone 52 will not be able to reflect light out of the bobbin If, however, weft exhaustion is approaching and that part of the bobbin adjacent to the cone is uncovered, light will be projected through the slots I8 and |9 to the photocell 85 as indicated in Fig. 3. The beam of light, designated at L, will be suiiiciently strong to activate the photocell when the condition shown in Fig. 3 exists.

Fig. 'I shows a circuit which may conveniently be used .with my invention. The two binding posts 18 and 'Il are supplied with a source of power, preferably a lighting circuit. The solenoid 24 is controlled by a relay 12 having an armature 13 for engagement with a contact 14. When the relay is energized its armature engages the contact 14, whereupon current flows rin the following circuit: binding post 1|, wire 15, wire 18, armature 13, contact 14, binding post 11, wire 11', solenoid 24, and wire 18 to the other binding post 'IILv When this circuit is closed the solenoid 24 initiates a replenishing operation of the loom as already described.

The relay 12 is controlled by the joint action of the photoelectric cell 55 and an electronic tube 88, together with resistances and a condenser, as shown in Fig. 7. Three resistances are connected in series across the source of power as follows: binding post 18, wire 8|, resistance R', binding post 82, wire 82', resistance R2, wire 83, resistance R3, wire 84, and wire 15 back to the other binding post 1|. Resistances R', R2 and R8 may be of the order of 5,000, 4,000 and 1,000 ohms, respectively, and

` resistance R3 is variable. The anode 85 of the photoelectric cell is connected by wire 86 to post 82, while the cathode 81 of cell 65 is connected by a wire 88 to a binding post 89 electrically connected to the control grid G of the gas 'filled thyratron electronic tube 80. The cathode C of the tube is connected by wire 90 to wire 83. and the shield grid SG of tube 80 may be connected to wire 8|) so that it will be at the same potential as the cathode, Tube 80 is preferably of the indirectly heated type and the iilament F for heating the cathode may be heated in any approved manner not indicated in Fig. 7.

A high resistance R4 of the order of A10 meghoms is connected between binding post 89 and a sliding contact 8| of resistance R3, and resistance R5 is employed to prevent too large a current frompassing through the relay'and plate of .the tube 80.

The sliding contact 8| is adjusted until the control grid Gis just negative with respect to the cathode of tube 88, under the conditions of illumination of tube 65 existing in the loom and without illumination of the cathode 81 by means of the beam of light L. Under these conditions the tube 88 is held inactive and the relay 12 is dead. Whenever the beam of light Aexcites the tube 65, however, as indicated in Fig. 3, there will be a change in the voltage drop across the high resistance R4 with a corresponding change in the grid G, whereupon current can flow through the tube to energize the followingcircuit: binding post 10, wire 8|, wire |00, resistance R5, wire IDI, relay 12, wire |02, plate P through the tube to the cathode C, wire 90, wire 83, resistance R3, wire 84, and wire to binding post 1|. This circuit Will remain activated while the lay is in theforward part of its movement yand will be closed long enough to enable the relay to effect complete energization of the solenoid 24.

As shown herein the solenoid 24 is operated directly by power taken from the binding posts 18 and 1I, but I do not necessarily wish to be limited to this arrangement, since it has been the practice in the past to energize the solenoid by means of a transformer not shown herein but under control of some such contact means as I3 and 1H.

The tube 80 and the relay 12, together with the resistances and the small condenser C in parallel with the relay to prevent chattering thereof, may be located within a casing or box K mounted as indicated in Fig. 1 on some convenient part of theloom frame. It is not essential that the box K be secured to the loom, and if desired in order to avoid vibration due to loom operation, the box may rest on the floor under the loom.

From the foregoing it will be seen that I have provided a photoelectrically controlled electric detector system for a loom wherein the beam of light for the operation of lthe cell 65 moves outwardly from a point within a transparent bobbin. It will further be seen that the source of light is directly mountedl on the lay in such position that it will cause a beam of light to fall on the cone 52 whenever the shuttle is properly boxed.

Furthermore, the inclined guide 31 which is very similar to those heretofore used is provided with a light reflector 38 which is a part of the optical system of the invention. Photoelectric cells ordinarily generate very small currents when stimulated by a beam of light, but I have found with an arrangement such as set forth hereinbefore that such light as gets through the front part of the bobbin and falls on the tube 65 is sufficient to cause a change in the potential of the grid of tube 8|] with resultant firing or operation of 'the latter. The cone 52 need not necessarily be formed exactly as shown in the drawings, nor will it be essential in all' uses to which theinvention can be put to have the light transmitting tube 55 interposed between the lamp 58 and the reflector surface 38. A1so, the photoelectric cell 65 is shown herein as mounted on the lay, but this is not essential. When so located, however, a considerable time is afforded for the energization of the relay.

Having thus described my invention it will be seen that changes and modifications may be made therein by those skilled in the art without departing from the spirit and scope of the invention and I do not wish to be limited to the details herein disclosed, but what I claim is:

1. In a weft detecting system for a loom having means to effect a change vin loom operation when a photoelectric cell forming part `of the system is energized by a beam of light, a bobbing in detecting position havingt a zone thereof to be detected formed of transparent material, a source of light, and means within the bobbin ,on which light from said source'parallel to the bobbin axis falls and from which light is reflected through said zone onto said photoelectric cell to energize the latter when said zone is depleted of weft.

2. In a weft detectin-g system for a loom having means to effect a change in loom operation when the photoelectric cell forming part of the system is energized by a beam of light, a bobbin in detecting position having a zone to be detected formed of transparent material, and means within the bobbin adjacent to said zone providing a reflector surface so disposed that a beam of light projected parallel to the axis of the bobbin is reflected laterally of and through said zone of the bobbin onto said photoelectric cell to energize the latter when said zone of the bobbin is depleted of weft.

3. In a weft detecting system for a loom having means to effect a change in loom operation when a photoelectric cell forming part of the systern is energized by a beam of light, a bobbin in ,detecting position having a zone to be detected formed of transparent material, said bobbin having a head and a bore extending thereinto from the head axially along said zone, and means on the bobbin providing a reflector surface located along said zone and at that end of the bore remote from the head, said reflector surface so disposed that a beam of light projected through the bore and onto said reflector surface will be 'reflected from the latter through said zone of the Aposed that light projected parallel to the axis of the bobbin and impinging on said reflector surface is reflected laterally through said zone onto the protoelectric cell to energize the latter when said zone is depleted of weft.

5. In a weft detecting system fora loom having a shuttle in detecting position, the loom havling means to effect a change in loom operation when a photoelectric cell forming part of the system is energized by a beam of light, bobbin holding means in the shuttle, a bobbin formed of inherently transparent material and having a head held by said bobbin holding means, the latter being capable of holding the bobbin in any angular position of the bobbin with respect to the axis thereof, and means 'within the bobbin from which a beam of light parallel to the bobbin axis can be reflected through the bobbin onto.

the axis of the bobbin, and means within the' bobbin providing a conical reflector surface, said conical surface being so disposed that the beam of light projected parallel to the axis of the bobbin toward` said reflector surface will be reflected laterally through the bobbin onto said photoelectric cell to energize thev latter when the bobbin is depleted of weft.

'1. In a weft detecting system for a loom having a shuttle in detecting position, the loom hav- 7 ing means to effect a change in loom operation when a photoelectric kcell forming Dart of the system is energized by a beam of light, means providing a reflecting surface carried 'by the shuttle, a bobbin formed of inherently transparent material held within the shuttle, means within the bobbin providing a reflector surface, and a source of light, said source of light, reflecting surface and reflector surface being so related that light from said source is reflected bygthe reflecting surface onto said reflector surface and from the latter laterally through the bobbin onto said photoelectric cell to energize the latter when the bobbin is depleted of weft.

8. In a weft detecting system for a loom having a shuttle in detecting position, the loom having means to effect a, change in loom operation when a photoelectric cell forming part of the system is energized by a beam of light, an inclined bobbin guide on the shuttle, a bobbin held within the shuttle adjacent to said guide, said guide being formed with a reflecting surface vand the bobbin being formed of inherently transparent material and having a reflector surface therein, and a source of light so related to said A reflecting and reflector surfaces that light from said source is reflected from said reflecting surface to said reflector and from the latter laterally through said bobbin onto said photoelectric cell to energize the latter when the bobbin is depleted of weft. i

9. In a weft detecting system for a loom having a shuttle in detecting position on the loom lay, the loom having means to effect a change in loom operation when a photoelectric cell forming part of the system is energized by a beam of light, a source of light mounted on the lay, a bobbin within the shuttle formed of transparent material and having an internal reflector, and means on the shuttle providing a reflecting surface so related to said source and reflector that a beam of light from said source is projected along the axis of the bobbin to said reflector and from the latter laterally through the bobbin onto said photoelectric cell to energize the latter when the bobbin is depleted of weft.

10. In a weft detecting system for a loom having a shuttle in detecting position, the loom having means to effect a change in loom operation when a photoelectric cell forming part of the system is energized by a beam of light, means on the shuttle providing a combined bobbin guide and reflecting surface, a bobbin in the shuttle having a barrel formed of transparent material, means within the bobbin adjacent said barrel providing a light reflector, and means to direct a beam of light against said reflecting surface, said means, reflecting surface and reflector being so related that light from said means is reflected from the reflecting surface onto said reflector and laterally from the latter through the bobbin barrel onto said photoelectric cell to energize the latter when the bobbin barrel is depleted of weft.

- of light from said source falling on the reflecting surface is reflected toward the reflector and from Te latter laterally through the bobbin for energization of the photoelectric cell when the bobbin'is depleted of weft.4

12` The combination of a shuttle and a bobbin held therein and formed of transparent material, means on the shuttle providing a reflecting surface, and means within the bobbin providing a light reflector so disposed that a beam of light extending from said reflecting surface onto said reector is reflected laterally through the bobbin.

13. In an electric weft detecting system for a loom having a lay provided with a shuttle box to hold a shuttle in detecting position, a source of light mounted on the lay, a photoelectric cell mounted on the lay and forming part of said system and eective when energized by a beam of light to cause the system to initiate a change in loom operation, a bobbin having a weft carrying transparent zone, and means within the bobbin adjacent to said zone constituting a light reflector, said source, photoelectric cell and bobbin being so related that when the shuttle enters said box and comes to rest relatively to said box in detecting position light from the source will impinge on said reflector4 and be reflected from the latter through the transparent zone of the bobbin onto said photoelectric cell and energize the latter when said zone is depleted of weft. 14.In an electric weft detecting system for a loom having a lay provided with a shuttle box to hold a shuttle in detecting position, a source bin adjacent to said zone, and means on the shuttle provided with a reflecting surface, said source, photoelectric cell, reflecting surface and reflector being so related that when the shuttle enters the box and assumes detecting position a beam of light from said source is directed onto said reflecting surface and from the latter to said reflector in the bobbin andthence outwardly through the bobbin zone to said photoelectric cell to energize the latter if said zone is depleted of weft.

15. In an electric weft detecting system for a bobbin changing loom having a lay provided with a shuttle box to hold a shuttle in detecting position, a source of light mounted on the lay, a photoelectric cell mounted on the lay and forming part of said system and effective when energized by a beam of light to cause said system to initiate a change in loom operation, an inclined bobbin guide on the shuttle having a reflecting surface, a bobbin held within the shuttle and having a weft carrying zone thereof to be detected made of transparent material, and means within the bobbin adjacent to said zone formed as a light reflector, light from said source mpinging on said reflecting surface and being reflected therefrom to said reflector and thence laterally through the transparent zone onto said photoelectric cell to energize the latter when the shuttle is in detecting position and said zone is depleted of weft.

16. In an electric weft detecting system for a loom having a lay provided with a shuttle box to receive and hold a shuttle in detecting position, an illuminated electric lamp mounted on the lay 'and moving therewith, a photoelectric cell mounted on the lay and moving therewith. and forming part of saidsystem and effective when energized by a beam of light to cause said system to initiate a change in loom operation, means inthe shuttle providing a downwardly inclined reecting surface, a bobbin in the shuttle having a weft carrying zone to be detected made of transparent material, a reflector within the bobbin adjacent to said zone, and a light transmitter on the lay having one end thereof adjacent to said lamp and having the other end thereof in the bobbin adjacent to said barrel formed withV a reector so disposed that light projected parallel to the axis of the bobbin toward said reflector is reflected laterally throughisaid transparent barrel.

18. In a bobbin, a head for said bobbin having rings by which the bobbin can be held in any angular position with respect to the bobbin axis,

a barrel for the bobbin adapted to receive weft and formed of transparent material, and a conical reflector within the bobbin adjacent to said barrel and so disposed that abeam of light projected parallel to the axis of the bobbin ontosaid reflector will be reilected laterally through said transparent zone.

19. A bobbin formed with a transparent weft carrying barrel and having an axial bore extending along the barrel, and means at the inner end of said bore adjacent to said barrel formed with a light reector so disposed that light projected through said bore and onto said reflector is reilected laterally through the barrel.

20. In a weft detecting system for a loom having means to eiect a change in loom operation ywhen a photoelectric cell forming part of the system is energized by a beam of light, a bobbin in detecting position lhaving azone thereof to be detected formed of transparent material, and means within the bobbin from which a beam 0f light parallel t0 the bobbin axis is reected through said zone onto the photoelectric cell to 10 energizethe latter when said zone is depleted of weft.

21. In an electrical weft detecting system for a loom having a lay provided with a shuttle box to receive a shuttle and hold the latter in weft detecting position, a source of light on the lay,

a photoelectric cell on the lay forming part of the system and effective when energized by a beam of lightI to cause said system to initiate a change in loom operation, and light reflecting and transmitting means carried by the shuttle and including twok reflectors and a transparent bobbin, said means eiective when the shuttle moves to said weft detecting position to complete an optical system between said source and said photoelectric cell including a beam of light betweenthe reflectors parallel to the bobbin axis to energize the photoelectric cell if the bobbin is depleted of weft, to the end that said optical system is operative throughout the time the shutle with thedepleted supply of weft is in said box and in weft detecting position.

22. A bobbin formed of transparent material, and means within the bobbin from which a beam of light within the bobbin and parallel to the bobbin axis is reflected laterally through the transparent bobbin.

OSCAR V. PAYNE.

REFERENCES CITED The following references are of record in the ille of this patent:

v UNITED PATENTS Germany ..-June 7, 1933 

